DOLBY B-TYBE NR PROCESSOR
S1A2271B01
1
INTRODUCTION
The S1A2271B01 is a monolithic integrated circuit designed for
use in Dolby*B-type noise reduction systems.
FEATURES
Few external components
Low quiescent circuit current (Typ ICCQ = 5.3mA)
High crosstalk rejection ratio
Builtin NR-switch, REC/PB-switch
Recommended supply voltage: V
CC
= 8V
-
16V
ORDERING INFORMATION
*
"
Dolby
"
and the double-D symbol are trademarks of Dolby Laboratories Licensing Corporation.
This IC is available only to licensees of Dolby Laboratories Licensing Corporation, San Francisco, from whom
licensing and application information must be obtained.
Device
Package
Operating Temperature
S1A2271B01-D0B0
16
-
DIP
-
300A
-
30
C
-
+ 85
C
S1A2271B01-S0B0
16
-
SOP
-
225A
16
-
SOP
-
225A
16
-
DIP
-
300A
S1A2271B01
DOLBY B-TYBE NR PROCESSOR
2
BLOCK DIAGRAM
RIPPLE
FILTER
R-CONSTANT
RIPPLE
FILTER
9
REC IN2
11
14
16
15
5
2
7
4
13
12
10
BUFFER
VCA & HPF
RMS
DETECTOR
BUFFER
GAIN
FACTOR
CONTROL
SWITCH
VOLTAGE
REGULATOR
VCA & HPF
RMS
DETECTOR
V
CC
PB IN2
PB OUT2
REC OUT2
REC OUT1
PB OUT1
PB IN1
REC IN1
NR SW
R/P SW
GND
6
8
3
1
RIPPLE
FILTER
DOLBY B-TYBE NR PROCESSOR
S1A2271B01
3
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS (Ta = 25
C)
NOTE: Derated above Ta = 25
C in the proportion of 10mW/
C
Characteristic
Symbol
Value
Unit
Supply Voltage
V
CC
16
V
Power Dissipation
P
D
750
mW
Operating Temperature
T
OPR
-30
-
+85
C
Storage Temperature
T
STG
-40
-
+125
C
1
2
4
REC OUTPUT1
RIPPLE FILTER
PB OUTPUT1
REC/PB CONTROL
3
5
6
8
R-CONSTANT
PB INPUT1
GND
REC INPUT1
7
16
15
13
REC OUTPUT2
RIPPLE FILTER
PB OUTPUT2
NR CONTROL INPUT
14
12
11
9
RIPPLE FILTER
PB INPUT2
Vcc
REC INPUT2
10
S1A2271B01
S1A2271B01
DOLBY B-TYBE NR PROCESSOR
4
ELECTRICAL CHARACTERISTICS
(Ta = 25
C, Vcc = 12V, f = 1kHz, 0dB = 245mW (
-
10dBm) at REC OUT, unless otherwise specified)
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
Quiescent Citcuit Current
I
CCQ
REC mode, NR-off, V
I
= 0
3.5
5.6
7
mA
Buffer Voltage Gain
G
V
REC mode, PB out = 0dB
25
27
29
dB
NR-REC Boost
G
V(BST)
RECout =
-
25dB, f = 500Hz
1.4
2.9
4.4
dB
RECout =
-
25dB, f = 2kHz
5.5
7.0
8.5
dB
RECout =
-
25dB, f = 5kHz
3.9
5.4
6.9
dB
RECout =
-
40dB, f = 10kHz
9.0
10.4
11.9
dB
RECout = 0dB, f = 10kHz
-
1.1
0.4
1.9
dB
NR-Boost Balance
CB
NR-REC boost CH to ratio
-
0
1
dB
MAX.RECout level
V
O (MAX)
REC mode, NR-off THD = 1%
14
15.9
-
dB
REC Output Voltage
THD
REC mode, NR-off
RECout = 10dB
-
0.04
0.2
%
REC mode, NR-on
RECout = 10dB
-
0.04
0.3
%
NR-effect S/N
S/N
REC mode, R
G
= 2.2K
Filter = CCIR/ARM
65
69
-
dB
Crosstalk
CT
NR-off, OUTPUT = 0dB
PB to REC
-
-
70
-
60
dB
CH to CH, NR-off
OUTPUT = 0 dB
-
-
70
-
60
dB
Input Impedance
Z
I
-
30
47
60
K
Switch Control
V
CTL
High mode
2.4
-
-
V
Voltage
Low mode
0
-
0.4
V
Input Level
REC V
I
REC mode, NR-off
RECout = 0dB
-
32
-
30
-
28
dBm
PB V
I
PB mode, NR-off
RECout = 0dB
-
32
-
30
-
28
dBm
Output Level
V
O
REC mode, NR-off
RECout = 0dB
Testpoint = PB output
489
549
616
m V
DOLBY B-TYBE NR PROCESSOR
S1A2271B01
5
TEST CIRCUIT
S1A2271B01
1
2
3
4
7
12
11
10
9
8
5
6
14
13
16
15
1
F
R/P
REC
OUTPUT1
100k
0.68
F
(10%)
1
F
PB
OUTPUT1
100k
1
F
REC
INPUT1
47k
(2%)
1
F
2.2k
2.2k
PB
INPUT1
1
F
REC
OUTPUT2
100k
0.68
F
(10%)
1
F
PB
OUTPUT2
1
F
REC
INPUT2
1
F
PB
INPUT2
100k
100
F
Vcc
REC
PB
4.7k
15k
NR
OFF
ON
2.2k
2.2k
S1A2271B01
DOLBY B-TYBE NR PROCESSOR
6
DOLBY B-TYBE NR PROCESSOR
S1A2271B01
7
S1A2271B01
DOLBY B-TYBE NR PROCESSOR
8
APPLICATION INFORMATION
Power Supply
The S1A2271B01 can be operated at 8V - 16V with a single power supply, and 4V - 8V with a dual power supply.
Switch Control Voltage
All functions of S1A2271B01 are controlled by internal electronic switches. The function switch is operated by the
DC voltage of NR and R/P control pins.
Reference Level
The reference output level of the Dolby noise reduction system is defined as Dolby level. The Dolby level of
S1A2271B01 is 245mV (
-
10dBm) at f = 400Hz.
NR, R/P
V
H
V
L
Condition
PB
REC
NR-off
NR-on
Single
Dual Power
V
H
2.4V
V
L
0.4V
V
H
V
EE
+ 2.4V
V
L
V
EE
+ 0.4V
5
6
7
8
12
11
10
9
S1A2271B01
+V
EE
+V
BB
GND
Dual power connection
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